Tuesday, January 10, 2017

Problem Solving with the Velocity Graph

Figuring out as much stuff as possible when you only know acceleration and change in position.


Monday, January 9, 2017

Elevator Conclusions

In the first part of class on Friday, we established Cameron/Huff's Law, "The Fu and acceleration point in the same direction.





In the elevator activity, we drew velocity v. time graphs that made it look like the acceleration would be upwards during part #2 and downwards during part #4.
We then took a closer look at what the FBD and FAD would need to look like for part #2, and settled on either C or D because their FADS had Fu's that point upwards (A and B had FADs that showed balanced forces).

We can analyze the motion of the elevator based on the amount of UnBalanced Force the guy is experiencing.  Given that C and D are the only options with UnBalanced Forces, and they both show an UnBalanced force of 55 lb directed up, they'll both result in the same acceleration for the guy.  We need to use conversion factors to make this problem manageable.  First, since the scale reads 157 pounds when he first steps on it, we can use the knowledge that 1 kg weighs 2.25 lbs to determine that his mass is around 71 kg.  Then, we can use the understanding that 1 lb is roughly 4.5 Newtons in order to determine that the Fu of 55 lb would be 245 Newtons.  Using a=Fu/m we can then find the acceleration by taking the 245 N divided by 71 kg of mass.  The guy is accelerating at 3.45 m/s/s at that point in time.  Use this process as you work through the problems on the worksheet.  Good luck!




Tuesday, December 20, 2016

Thursday, December 15, 2016

Current level of essential understandings for Constant Acceleration Particle Model

Monday, December 12, 2016

Video Analysis: No Strings Attached and Strings Attached

This tutorial will give you the basics on video analysis with logger pro.



Then you'll need to analyze each of the two videos below:


No Strings Attached

Strings Attached





IN CASE I DIDN'T MENTION IT IN THE VIDEO, YOU DON'T HAVE TO PUT A DOT ON EVERY FRAME, YOU CAN SKIP AHEAD A COUPLE OF FRAMES BETWEEN DOTS AND IT WON'T HURT YOUR GRAPH.

Bring a print out of the velocity vs. time graphs for your video analysis to class on Thursday.  Additionally, draw FBDz for the strings attached video for (1) the time before the blower has been turned on, (2) for the time a short while after the blower has been on, and (3) for the time after the mass has hit the floor. Additionally, you'll need the FBD for the no string attached video.